Electrochemical assay for saccharide-protein interactions using glycopolymer-modified gold nanoparticles

A novel recognition element, made of electroactive glycopolymer-modified gold nanoparticles (GM-GNPs), was synthesized and used in an electrochemical assay of saccharide-protein interactions for the detection of concanavalin A (Con A). The electroactivity of the mannose-based GM-GNPs was investigated, and an electrochemical Con A assay system with a disposable screen printed carbon strips was proposed. A complex containing GM-GNPs was formed by a recognition reaction between the mannose-based glycopolymer and Con A. The complex was detected by the pre-oxidation of the GNPs and following reduction scans using differential pulse voltammetry (DPV). Under optimal conditions, a linear relationship between the DPV peak current intensity and Con A concentration was shown within an analytical range of 10-10,000 ng/mL. Our proposed new electric approach provides an interesting tool for the analysis of saccharide-protein interactions. (C) 2011 Elsevier B.V. All rights reserved.